Posted
by
kdawson
on Friday October 22, 2010 @11:53AM
from the boson-walks-into-a-church dept.

eldavojohn writes "Graphene has gotten a lot of press lately. The Nobel prize-winning, fastest-spinning, nanobubble-enhancedsilicon replacement is theorized to have a new, more outlandish property. As reported by Technology Review's Physics Blog, graphene should be able to create mass inside properly formed nanotubes. According to Abdulaziz Alhaidari's calculations, if one were to roll up graphene into a nanotube, this could compactifiy dimensions (from the sheet's two down to the tube's one), and thus 'the massless equations that describe the behavior of electrons and holes will change to include a term for mass. In effect, compactifying dimensions creates mass.' What once would require a massive high-energy particle accelerator can now be tested with carbon, electricity, and wires, according to the recent paper."

It seems to me that it's poorly worded. As far as I can tell, it's not 'creating mass' so much as it is 'creating dependency on mass'

Normally the equations governing movement of electrons are independent of mass. In graphene it appears we should be able to make it dependent on the mass of the electron.

So I believe the article is saying that they believe they can make some particles that didn't appear to have a mass have a new equation for movement that reveals a mass for them. The article mentions that there's a theory that these particles didn't have a mass before this point; that the actual changing of rules that govern movement creates the mass.

I like to think of it as the equivalent of creating charge. You're not actually making anything; you're just moving electrons/protons so they're out of balance. Essentially this could be the same thing with gravity.

Now if this could be reversed to make something mass-less, that would be interesting

Let us say you are hanging outside by holding on the window bars a long train (make it infinitely long train, who cares? it is theoretical physics, Also make it a train in India because most trains in Europe and USA have glass windows with no grab holds) and the train is moving with some speed. The outer walls of the train would not grab you and hold you against gravity. You have to hang on with your dear life. But if you curve the train track to make it circular, you will experience a centrifugal force that pins you to the outer wall of the train, and you can even let go of the window bars and shout, "Look! Ma! No hands".

Of course you know that centrifugal force is not a real force, but a pseudo force you conjure up if you are working on a reference frame attached to the train. From an inertial frame of reference, your velocity is being changed constantly. Change in velocity is acceleration. The change in direction would be towards the center of the circular track. That acceleration is centripetal acceleration. The train is exerting a force centripetal force on you. The reaction from your body on to the train for that force times friction coefficient gives you the force that is holding you still stuck like a fly on the wall of a train moving in a circular track.

As one who has spent years hanging on to the window bars of trains and buses in Chennai, India, let me tell you, no matter how many Einsteins tell you that is a
pseudo force, it felt real and that I am still living, not having been run over decades ago by the next bus or train proves that centrifugal force is real. Not pseudo.

Similarly the fermions seem to be having a mass to satisfy some equation in some frame of reference after some coordinate transformation. But really it is not creating any mass.

I don't think they're suggesting more carbon atoms are being created out of thin air. It seems like they're saying it would have the same size and number of particles, but its mass would go up -- i.e. it would have more inertia. Lots of models in physics require "gaining mass" -- i.e. gaining inertia.

Einstein predicts as you accelerate to the speed of light, you gain mass in your reference frame -- i.e. it becomes harder and harder to accelerate yourself further because you appear to be getting infinitely massive. Einstein is not suggesting that your belly expands and you start generating more particles. He's using "mass" interchangeably with "inertia". Greater mass == greater inertia, when all else is kept constant.

Similarly, the experiment with graphene suggests that a proper configuration of it will yield something with greater inertia (i.e. greater mass) than its constituent masses imply.